After futzing with several non-captive real SIP phones[*] (SIPDroid, Linphone, 3CX) I got involved in the testing of this new app. The author Regis Montoya, has done a great job, and it appears he's only getting started. After some testing, I decided it is a keeper, and decided to make this my "learn how to write Android apps" project. So now I'm involved in its development (small things for now). Here are some links: CSipSimple Project Home Page CSipSimple pre5 Download Page (with QR box) You'll need to enable apps from unknown sources. There is no help at all, but if you're familiar with setting up real SIP (as opposed to Fring, etc.) you should be able to figure it out. Running on my HTC INcredible/Verizon via 3G and WiFi. Be sure to set up STUN if you want to use WiFi!